High-frequency contact device



June 24, 1930. A. M. 'TROGNER 1,766,049

HIGH FREQUENCY .CONTACT DEVICE Filed March 9, 1929 Mar.0 ymzr kuayvm Patented June 24,- 1930 UNITED sT 'rEs fATENT OFFICE Antenna M. TROGNER, or EAST ORANGE, NEW JERSEY, AssIeNoR, BY MEsNE ASSIGN- mars, 'ro FEDERAL TELEGRAPH ooMrANY, A CORPORATION E CALIFORNIA HIGH-FREQUENCY CONTACT DEVICE Application filed March 9,1929. Serial No. 345,855.

My-invention relates broadly to means for establishing electrical connection between a movable member and a stationary surface,

. and more particularly to a device for improving the efficiency of high frequency electrical apparatus.

One of thevobjects of m invention is to provide a construction 0 electrical conductor for high frequency apparatus whereby a lar e conductive area for the distribution of high frequency currents is provided for establishing connection between 'a stationary conductive surface and a rotatable member movable with respect thereto. I Another object of my invention is to provide a construction of electrical connector for the end of the rotatable shaft member wherein a plurality of independent paths are provided for distributing high frequency energy from the central rotatable shaft to a stationary surface, the paths extending from the shaft to the stationary surface so disposed relative to each other as to have practically equal radio frequency resistance. A further object of my invention is to provide a construction of electrical connector disposed between a rotatable shaft and a stationary surface, the connector being-provided with a multiplicity of spaced sectors each of which carry a substantially equal distribution of current between the rotatable shaft and the stationary surface.

Otherand further objects of my invention reside in the construction of an electrical conductor described in the specification hereinafter following by reference to the accompanying drawings, in which:

Figure 1 is a perspective view of the high frequency conductor of my invention; Fig

2 is aplan view of the high frequency conductor of my invention and Fi 3 is a cross-sectional view of the high requency.

conductor of my invention. I

In electrical signaling systems and in genoral-wherever high frequency signaling energy is employed, there is a considerable loss of efficiency in poor conducting surfaces. It is wellknownthat when high frequency energy is conducted by means of metal, such high frequency energy travels on the surface of the conducting member, thedegree of penetration becoming less as the frequencyv of the energy is increased. It is therefore evident that the cross-sectional area of radio frequency conductors need not be to conduct radio frequency energy from one surface to another. It therefore becomes necessary to provide improved radio frequency. conductors that will have large surface areas and hence offer a low resistance to radio frequency energy. It frequently happens that it is desirable to cause a transfer of radio frequency energy from a movable member to a stationary'membeix Such transfer is desirable when capacities are employed which are adjustable and when a movable coil is employed in inductive relation with a second coil. It therefore is necessary to provide an efficient conducting system which will insure low radio frequency energy loss due to surface resistance.

Referring to the drawings in more detail,

I have'illustrated my invention as applied.

to the rotary shaft of a variable condenser, but it will be understood that the device of my invention may be applied to various forms of high frequency electrical apparatus where it is necessary to establish a connection between a stationary surface and a rotatable shaft member. The variable condenser is provided with a plurality of rotor plates 2 carried by rotatable shaft member 1 on the end of which there is secured for movement with the shaft the electrical conductor of my invention illustrated at 3. The 100 electrical conductor 3 is constructed from resilient metallic material and is secured to the end of shaft 1 by nut member! which is screw threaded on the end of the shaft 1 projecting as represented at 5 through the metallic end plate 6. The plate 6 forms a bearing for the end of the shaft 1. Normally all of the high frequency energy which passes to or from the rotor plates 2 must e distributed over the journaled end 5 of shaft 1 and through the bearin 7 in late -6,'which results in considerable oss an secured at its center" to t inefliciency in hi h frequency ap aratus.-

. However, the con uctive member 3 o my invention is disposed between the shaft 1 and the plate 6 in such manner as to provide a multiplicity of distribution paths for the high frequency currents. The device 3 conin angularly osed end portions with the extreme ed t ereof engaging the surface of said con uctive plate, each of said edges extending in a plane substantially tan cut to a circle drawn through the smallest ra ius of the sector to which the'ed es connect.

ARTHUR M. ROGNER.

sists of resilient metal having a substantially circular contour and composed of a plurality of radiating sector ortions 8. The

sector portions 8 are divide by radial slots 9. The portions 8 are relatively narrower adjacent the center as represented at 10 and are substantially wider at 11. The exterior ends of the sectors are bent downwardly as represented at 12 to frictionally engage the passing through the shortest radius of the sector. I have indicated such a curve by dotted lines at 15 in Fig. 2. The edges 14 of the sectors are thus angularly disposed one to the other providin an angularly dispomd plate which actual y sweeps the surace 0 the conductive late 6 as the shaft 1 is rotated, thus. establi ing good electrical connection with substantially negli 'ble loss. The device of m invention as been found to be extreme practical in its construction, and while I ferred embodiment of my invention, Idesire that it be understood that modifications may be made and that no limitations upon my invention are intended other than are im-- posed by the scope of the a pended claim.

What I claim as new an desire tosecure by Letters Patent of the United States is: A device for establishing connection between a rotatable shaft and a conductive plate comprising an inte a1 metallic sheet i e rotatable shaft and being-constituted by a multiplicity of radially positioned sectors each terminating have described a pre-.. 

